How Dangerous is Bird Flu (H5N1) to Global Public Health? Part 2 (Oct 17, 2011 - Nov 25, 2012)

[Laidback Al]

Reconsidering Human H5N1 Cases in 2009 in Indonesia

The year 2009 probably represents a low point in the relationship between WHO and government of Indonesia regarding the timely report of human cases of H5N1. Under IHR, member countries such as Indonesia are requested to immediately report any confirmed cases of H5N1. However, throughout the year of 2009 Indonesia failed to report human cases to WHO in a timely manner. On December 28, 2009, DEPKES, the Indonesia Public Health authority, quietly report a total of 20 cases for the year. Ultimately WHO now reports a total of 21 human cases from Indonesia for 2009, with only 2 survivors that year. (link)

Public information on these 21 cases is limited. WHO has not published any demographic or epidemiological information about these cases. However, media reports since 2009 sometimes provide information about these cases years later. For example, a local media report in 2011 clearly indicates that there was a family cluster of three confirmed H5N1 cases in West Jakarta in 2009. (link)

And now in 2012 another media article on bird flu in Jakarta reports that there were 10 confirmed H5N1 cases in the greater urban area of Jakarta in 2009. Of these cases, only two survived.

. . . Although the Jakarta Health Service data shows the number of cases of bird flu continues to decline, but the number of deaths from this disease is high. Data on the Jakarta Health Agency noted, during 2009, eight of 10 patients suspect bird flu death (84%). In 2010 the amount was decreased to 3 patients, but all died (100%). . . .

http://m.inilah.com/read/detail/1855...dari-kota-lain

Because WHO reports only two survivors among the 21 H5N1 cases in Indonesia in 2009, they must have been from Jakarta. It seems that at least 10 of the 21 confirmed cases of H5N1 in Indonesia in 2009 occurred in the urban Jakarta area including the family cluster.

Why discuss this now in 2012? Isn’t it almost ancient history?

First, it shows that H5N1 infections in Indonesia in 2009 were not just occurring in the countryside, but were common in urban settings in DKI Jakarta.

Second, had the H5N1 strain circulating in DKI Jarkarta in 2009 become easily transmissible, there would have been no stopping it in an urban environment. A “Tamiflu blanket” would have been ineffective. The failure of Indonesia to report these cases immediately would have hampered pandemic preparations elsewhere in the world. Thankfully the strain(s) didn’t mutate or change in 2009.

That is why we here at FluTrackers continually call for increased human and animal surveillance for H5N1 and other emerging infectious disease. While the world will not be able to stop the next pandemic, some advance warning might help us all better prepare for the outcome.

[Laidback Al]

If bird flu strikes in British Columbia you won’t hear about in the media

According to several media reports (FT link and link) the provincial government of British Columbia will soon make it a crime to publicly report disease outbreaks such as bird flu. According to the media reports the law requires that "a person must refuse ... to disclose... information that would reveal that a notifiable or reportable disease is or may be present in a specific place or on or in a specific vehicle." This means if you are aware of bird flu outbreak anywhere in the province, you cannot inform the media or post it on the internet.

You might ask why should we worry about this, after all, there is no bird flu in North America. A search of FluTrackers archive brings up this thread Canada - LPAI H5 Confirmed on 2nd Turkey Farm from 2009. More than 60,000 turkeys were culled in British Columbia in 2009 because of an outbreak of low pathogenic avian influenza. The 2009 outbreak was not the first avian influenza outbreak in the Fraser Valley in this province. Avian influenza outbreaks had previously occurred in the area as early as 2004.

If this new law is passed restricting public reporting of disease outbreaks in British Columbia, it may protect the poultry producers but will not protect the citizenry in the event of a jump from animals to humans. It seems that media transparency is less important than protecting the economic infrastructure of poultry farms in the province.

We have come to expect suppression of media reports on bird flu outbreaks in countries such as China and Indonesia. I never thought Canada would be the next country to suppress such media reports by catering to special interest groups at the expense of public welfare.

[Laidback Al]

New test for H5N1 developed, nearly 100% accuracy

There is some good news out of Singapore. Researchers at Experimental Therapeutics Centre (ETC), a division of Agency for Science and Technology Research (A*STAR), in conjunction with researchers from Tan Tock Seng Hospital (TTSH) have developed a new RT-PCR assay that can test for multiple strains of H5N1. According to press releases, this H5N1 test kit has been clinically validated by several hospitals in Southeast Asia. This test was co-developed by Dr. Masafumi Inoue, a Senior Research Scientist and Project Director of Technology Development from ETC and Dr. Timothy Barkham, a senior consultant of Laboratory Medicine from TTSH.

The current gold standard for H5N1 detection recommended by the World Health Organization (WHO) is only able to detect three out of the 10 distinct genetic groups (clades 1, 2 and 3). To detect all existing strains of H5N1 with the WHO detection method would not be possible. The made-in-Singapore H5N1 test kit, which is more accurately known as the H5N1 real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) assay, is the only detection kit currently available on the market that can accurately and rapidly detect all known strains of the H5N1 Avian Influenza A virus in a single test within a matter of hours.

http://www.news-medical.net/news/201...s-of-H5N1.aspx More media report links at this FT thread.

Hopefully, this test kit will be made widely available to local laboratories in regions with endemic H5N1. Local detection and identification of H5N1 infections within a few hours will undoubtedly save lives and perhaps help contain a local or regional outbreak.

[Laidback Al]

Are human H5N1 cases being underreported to the World Health Organization?

In the thread on H5N1 in Egypt, Sharon Sanders suggests the possibility that human H5N1 cases are now being underreported in Egypt.

Originally Posted by sharon sanders

If we look at both the FluTrackers human H5N1 case chart and the WHO Human H5N1 case chart we can see a large decrease in confirmed cases occuring since early 2011. If there are no more confirmed cases in Egypt in the next 5 months of 2012 (or only 1 or 2), then the numbers will tell us that the confirmed cases have dropped up to 75% in recent years.

Is this believable when there are ongoing poultry outbreaks?

A closer look at the WHO data on H5N1 cases in light of recent political and social events in Egypt and Indonesia may shed some light on the variability on H5N1 case numbers over time.

Background and Data

To date 607 human cases of H5N1 have been confirmed by WHO since 2003 (link). Although 19 human cases were reported in Hong Kong in 1997, WHO did not start reporting cases until 2003. Of the 607 case reported by WHO through July 6, 2012, almost 59% of these cases have been reported from just two countries, Indonesia with 190 cases and Egypt with 168 cases. The graph below plots the total number of WHO-confirmed H5N1 cases by year since 2003 (red line). The chart also shows the number of cases in each of these two countries as a percentage of total WHO reported cases for each of the years since 2003 (blue dashed lines).

Notably, there has been a general overall decrease in the number of reported H5N1 cases worldwide since 2006. Whether these lower case numbers represent a decline in human H5N1 infections or shortcomings in local surveillance and reporting is not known.

Between 2006 and 2008, Indonesia was reporting year-after-year increases in the proportion of worldwide cases. This increase peaked in 2008. The following year, 2009, the number of reported human cases in Indonesia dropped and has remained low ever since. It was in 2009 that Indonesia flaunted IHR and failed to notify WHO of H5N1 cases in a timely manner. This late reporting was a reaction to issues about the limited availability of H5N1 vaccines to Indonesia even though some of the vaccines were derived from locally identified strains of the virus. We do know that of the 20 H5N1 cases reported to WHO at the end of 2009 by Indonesia, there was at least one family cluster that thankfully did not produce a transmissible strain.

Egypt first exceeded Indonesia in the raw number of local human H5N1 infections in 2009. Every year since then, Egypt has reported more H5N1 cases than Indonesia. Between 2009 and 2011, Egypt was proportionally reporting more cases than Indonesia. However, for the first six months of 2012 that proportional difference between Egypt and Indonesia has dramatically decreased. Perhaps, the political turmoil in Egypt in 2011 has crippled the health system in that country as speculated by Sharon Sanders. It is also possible that the H5N1 surveillance network in Egypt has been disrupted resulting in fewer reported cases of H5N1.



Discussion

It is difficult to speculate whether the recent decline in worldwide reported H5N1 cases represented an actual decline in cases of human infection or if other political and social factors have conspired to restrict surveillance and reporting.

With media attention focusing on laboratory manipulation of H5N1 viruses over the past few months, there seems to be a renewed concern over an H5N1 pandemic. H5N1 is already endemic in animal populations in a number of countries including China, Vietnam, Indonesia, and Egypt. No one country wants to be associated with an H5N1 epidemic, and certainly none want to be recognized as the source of pandemic H5N1 strain.

Further epidemiological and virological research is needed to assess whether or not the recent declines of confirmed H5N1 cases represent absolute declines in infections or lax surveillance and deliberate misreporting of human cases in the countries where H5N1 is endemic.

[tetano]

The antigenic property of the H5N1 avian influenza viruses isolated in central China

Wei Zou, Jianjiang Ke, Jiping Zhu, Hongbo Zhou and Meilin Jin

For all author emails, please log on.

Virology Journal 2012, 9:148 doi:10.1186/1743-422X-9-148
Published: 6 August 2012
Abstract (provisional)
Background

Three influenza pandemics outbroke in the last century accompanied the viral antigen shift and drift, resulting in the change of antigenic property and the low cross protective ability of the existed antibody to the newly emerged pandemic virus, and eventually the death of millions of people. The antigenic characterizations of the viruses isolated in central China in 2004 and 2006-2007 were investigated in the present study.
Results

Hemagglutinin inhibition assay and neutralization assay displayed differential antigenic characteristics of the viruses isolated in central China in two periods (2004 and 2006-2007). HA genes of the viruses mainly located in two branches in phylogeny analysis. 53 mutations of the deduced amino acids of the HA genes were divided into 4 patterns. Mutations in pattern 2 and 3 showed the main difference between viruses isolated in 2004 and 2006-2007. Meanwhile, most amino acids in pattern 2 and 3 located in the globular head of the HA protein, and some of the mutations evenly distributed at the epitope sites.
Conclusions

The study demonstrated that a major antigenic drift had occurred in the viruses isolated in central China. And monitoring the antigenic property should be the priority in preventing the potential pandemic of H5N1 avian influenza virus.

http://www.virologyj.com/content/pdf...422X-9-148.pdf

[Laidback Al]

H5N1 Antigenic Drift in China

It is important to remember that the research showing antigenic drift of H5N1 HPAIV in China (abstract posted by tetano above) was from data collected in China in 2004 and from 2006-2007, almost five years ago.

Since then there have been additional H5N1 HPAI infections in China and elsewhere as show in the graph below from the most recent FAO global summary of H5N1 (January – March 2012 ) (link).



As noted by the FAO, because of data collections methods, local outbreaks in Indonesia are not comparable to the outbreaks graphed in the above figure. The outbreaks in Indonesia are depicted in Figure 7 in the same FAO report (shown below). It is clear that Indonesia continues to have an exceptionally high number of HPAI outbreaks every year.



The article by Wei Zou and colleagues reminds us of that continued, real time surveillance of HPAI outbreaks is critical if we are to monitor changes in H5N1 HPAI viruses that might give rise to a pandemic strain.

[sharon sanders]

Yesterday the Indonesia Ministry of Health updated their site with a new H5N1 bird flu death. This is the 9th death reported in Indonesia this year.

The case fatality for 2012 is 100%. This is not a believable statistic. How many cases are not being reported to the World Health Organization?

Our chart with links to WHO:


#183 - Male, 23, onset date December 31, hospitalized January 3, 2012, died January 7 - Jakarta province Death

#184 - Female, 5, family member of case #183, onset date unknown, hospitalized January 7, died on January 16 - Jakarta province Death

#185 - Female, 19, onset date February 8, hospitalized February 12, died on February 13 - Tangerang, Banten province (near Jakarta) Death

#186 - Male, 12, onset date February 11, hospitalized February 16, died on February 21 - Badung, Bali Death

#187 - Female, 24, onset date February 23, hospitalized February 24, died March 1 - Bengkulu, Sumatra Death

#188 - Male, 17, onset date February 28, hospitalized March 7, died March 9 - West Lombok, West Nusa Tenggara Death

#189 - Male, 2, onset date April 17, hospitalized April 21, died April 27 - Riau Province Death

#190 - Female,8, onset date June 18, hospitalized June 24, died July 3 - West Java Death

#191 - Male 37, onset date July 24, hospitalized July 27, died July 30 - Yogyakarta Province Death


--------------------------


Please also view this post about the H5N1 statistical anomaly in Egypt:


Are human H5N1 cases being underreported to the World Health Organization?

[Laidback Al]

Zoonotic Transmission of Influenza Viruses

In an article to be published in Veterinary Microbiology entitled “Dog to dog transmission of a novel influenza virus (H5N2) isolated from a canine,” researchers in China demonstrated that a novel H5N2 influenza virus can be transmitted by direct contact between dogs (link to abstract).

It is worth remembering that the only recent HPAI outbreak in North America was novel H5N2 in a poultry flock in Texas in 2004. No human cases were associated with this outbreak (link). However, possible poultry-to-human infection of H5N2 occurred in Japan in 2005 and was reported in 2008 in article in the Journal of Epidemiology (full text available here).

The recent outbreak of human cases of novel H3N2v in the USA has been attributed to swine-to-human transmission although there is now some evidence for limited human-to-human transmission of H3N2v (link).

It is a sobering reminder of how little we understand about zoonotic transmission of influenza viruses.

Credits to tetano for abstract link

[Laidback Al]

Antiviral treatment - H5N1

Determinants of Antiviral Effectiveness in H5N1 Avian Influenza.

J Infect Dis. (2012) doi: 10.1093/infdis/jis509 First published online: August 20, 2012

Chan PK, Lee N, Zaman M, Adisasmito W, Coker R, Hanshaoworakul W, Gasimov V, Oner AF, Dogan N, Tsang O, Phommasack B, Touch S, Swenson A, Toovey S, Dreyer NA.

Abstract

Background. Oseltamivir is widely used as treatment for H5N1 infection, but like any intervention, is not always effective.

Methods. Using Avian Influenza Registry data from ten countries (www.avianfluregistry.org), the risk of death in 215 patients with confirmed H5N1 infections and treated with oseltamivir is examined according to viral clade, age, respiratory failure, and adjunctive treatment with corticosteroids or antibiotics.

Results. The median age of cases was 18 years, and 50% were male. The highest fatality rate occurred in a country with clade 2.1 virus circulation, and the lowest, in countries with clade 2.2 (p<0.001). In univariate analyses, youth (≤5 years) and treatment within 2 days of symptom onset were protective against fatality. When accounting for all risk factors, early oseltamivir is particularly effective when initiated in the absence of respiratory failure (OR 0.17, p=0.04). Patients already suffering from advanced respiratory failure requiring ventilatory support at the time of oseltamivir initiation were more likely to die than patients who did not (p<0.001 ). Adjunctive therapy did not improve survival.

Conclusions. Oseltamivir is especially effective for treating human H5N1 infection when given early and before onset of respiratory failure. Effect of viral clade on fatality and treatment response deserves further investigation.

http://jid.oxfordjournals.org/conten...09.short?rss=1

A number of research articles and reports by specialists have demonstrated the efficacy of antiviral treatment of H5N1 with neuraminidase inhibitors within 48 hours of onset. It is unfortunate that H5N1 case information in the avian flu registry (www.avianfluregistry.org) is not open access and is controlled by a private, for-profit entity.

[sharon sanders]

It appears that www.avianfluregistry.org is owned by Outcome Sciences, Inc. who is owned by Quintiles Outcome.

One of the 2 principles:

"Dr. Gliklich is the editor of a textbook on the practical value of real-world data in medical practice, "Profiting from Quality: Outcomes strategies for medical practice," published by Jossey-Bass, Inc., in 1999. He is a Principal Investigator (PI) for the Outcome DEcIDE Center under the Agency for Healthcare Research and Quality's Effective Healthcare Program. In 2010, Dr. Gliklich was recognized by the trade journal PharmaVoice as one of the 100 most inspiring people in the pharmaceutical and life sciences industry."

Since the data base is private and is controlled by a pharma company, the findings of the study, which support the use of a pharmaceutical product, rest solely on the reputation of the study participants.


This means that......

[Laidback Al]

Is the USA taking steps to prepare for an H5N1 pandemic?

On June 7, 2012, the Public Health Emergency section of the Department of Health and Human Services made a low-key press release on the funding of human trials for a live attenuated H5N1 vaccine.

BARDA Contract 1

​​HHS support results in international influenza vaccine milestone Clinical trial among first in the world for live attenuated influenza vaccine for avian influenza

Thailand today became one of the first countries in the world to test an H5N1 avian, or bird, influenza vaccine in a needle-free, nasal spray formulation. This Phase I clinical trial of a live attenuated influenza vaccine, known as LAIV, to protect people from the H5N1 virus, resulted from international collaboration with health agencies around the world, including the U.S. Department of Health and Human Services’ Biomedical Advanced Research and Development Authority (BARDA). A Phase I clinical trial is the first step in testing new vaccines in humans. . . .

Through a grant to the WHO, BARDA has provided funding and technical assistance to support Thailand’s GPO as well as other developing countries. The grant supported building pilot scale manufacturing facilities to produce the vaccine, devising a clinical trial process to study the vaccine’s effectiveness in protecting people against avian influenza and a regulatory process to evaluate the vaccine, as well as conducting clinical trials in humans. . . .

The study and data analysis for this clinical trial are expected to be completed by May 2013.

Certainly, Thailand is an excellent choice for trials. Between 2004-2006, Thailand reported 25 human H5N1 cases. Also, given the anti-vaccine sentiment in the USA, clinical trials of a live attenuated H5N1 vaccine would probably not be popular, especially given the media storm over the recent H5N1 ferret tests and arguments over potential laboratory escapes.

BARDA Contract 2

Recently, on September 6, 2012, the Public Health Emergency section of the Department of Health and Human Services provided another press release relating to pandemic vaccine production.

New HHS contracts enhance pandemic preparedness BARDA takes historic steps with master vaccine seed lots, vaccines for pre-pandemic stockpile

The U.S. Department of Health and Human Services has awarded three-year contracts to all five U.S.-licensed influenza vaccine manufacturers to produce master vaccine seed stocks for viruses with pandemic potential before a pandemic occurs. The contracts also allow HHS to purchase cell-based vaccine in addition to conventional egg-based vaccine in a pandemic. Both steps are new in the department’s pandemic preparedness efforts. . . .

Since 2010, HHS has taken steps to increase national vaccine manufacturing capacity with nimble and flexible technologies, such as cell-based vaccine technologies. These technologies may assist HHS in providing more pandemic influenza vaccine sooner. Cell-based vaccine production could more easily meet surge capacity needs because cells could be frozen and stored in advance of an epidemic, or developed rapidly in response to an epidemic.

The contracts will be overseen by the HHS Biomedical Advanced Research and Development Authority (BARDA) and are awarded to Sanofi Pasteur of Swiftwater, Pa., Novartis in Cambridge, Mass. and Holly Springs, N.C., GlaxoSmithKline of Philadelphia, Pa., CSL Biotherapies of King of Prussia, Pa., and MedImmune of Gaithersburg, Md.

The contracts also support clinical trials and stockpiling of vaccine and adjuvants, enabling HHS to respond quickly to flu outbreaks and pandemics. Although current licensed seasonal flu vaccines do not contain adjuvants, clinical trials using adjuvants is an important part of pandemic preparedness. Adjuvants can be added to influenza vaccine to lower the amount of the active ingredient in vaccine, called antigen, needed for the vaccine to produce an immune system response. Adding adjuvant results in more doses of vaccine being available during a pandemic.

Initially HHS will commit a total of $4.4 million for the companies to produce master vaccine seed stocks and $7.3 million for the companies to store pre-pandemic vaccines.

Similar to these previous contracts, today’s contracts are flexible enough to be used to develop vaccine for emerging influenza strains. In addition to being used for the 2009 H1N1 vaccine, the previous contracts were used earlier this year to develop a vaccine against the new H3N2v influenza virus which has infected people coming in contact with pigs carrying the virus.

Human influenza pandemics continue to be a public health concern. An influenza pandemic occurs when a novel virus emerges in the human population, with no or low levels of pre-existing immunity, is readily transmissible from person to person. Since 2004, HHS has purchased and stockpiled H5N1 avian flu vaccine and new oil-in-water adjuvants from manufacturers based on annual assessments of novel influenza viruses with pandemic potential. . . .

This press release is vague regarding the actual contracts for pandemic virus research and development. On a blog from a web site that tracks USA military and defense issues, another perspective on these contracts emerges.

Posted on September 10, 2012

U.S. government takes threat of bird flu pandemic seriously; spends $25 billion for medical countermeasures

By John Keller

Evidently the U.S. government is taking the threat of a global bird flu pandemic very seriously, as the U.S. Department of Health and Human Services (HHS) has awarded five contracts collectively worth as much as $25.36 billion for medical countermeasures to the H5N1 avian influenza virus. . . .

To keep any potential H5N1 bird flu pandemic in check, HHS officials on 4 Sept. awarded contracts potentially worth $9 billion to Novartis Vaccines and Diagonostics Inc. in Boston; $8.2 billion to MedImmune LLC in Gaithersburg, Md.; $4.7 billion to Sanofi Pasteur Inc. in Swiftwater, Pa.; $2 billion to GlaxoSmithKline LLC in Philadelphia; and $1.5 billion to CSL Biotherapies Inc. in King of Prussia, Pa.

All contract awards are the maximum amount possible. The contract duration is three years with options for two additional years. Awarding the contracts was the HHS Biomedical Advanced Research and Development Authority (BARDA).

The companies will provide the U.S. government with vaccines, support, and medical storage not only for pre-pandemic medicine to help prevent the spread of the H5N1 virus, but also for medicines to treat the virus after it is contracted to alleviate symptoms and prevent deaths. . . .

So the question remains, Is the USA taking steps to prepare for an H5N1 pandemic or is it just being prudent?

[Laidback Al]

Pandemic triage should be a part of disaster medicine training

Tetano posted an abstract today for an article entitled "Disaster Curricula in Medical Education: Pilot Survey" (link). The authors conducted this study to evaluate the inclusion of disaster medicine in core curricula in medical training. The authors provide a disappointing conclusion.

Originally Posted by tetano

. . . Only a small percentage of US medical schools currently include disaster medicine in their core curriculum, and even fewer medical schools have incorporated or adopted competency-based training within their disaster medicine lecture topics and curricula.

Smith J, Levy MJ, Hsu EB, Levy JL. Disaster curricula in medical education: pilot survey. Prehosp Disaster Med. 2012;27(5):1-3.

link: http://journals.cambridge.org/action...ne&aid=8676183

Treating patients during the next pandemic would qualify as disaster medicine if the CFR begins to approach the CFR level from the 1918 pandemic. Every HCW and medical professional should receive training in disaster medicine. Every HCW and medical professional should understand that in the wake of a virulent pandemic, medical facilities will be strained to the limits, medicine will be in short supply, relief staff nonexistent, and a vaccine months away.

Medical educators owe it to their students to adequately prepared them for the next pandemic.

[Laidback Al]

Which country has the highest number of reported human cases of H5N1?

The second annual International Society for Influenza and other Respiratory Virus Diseases (ISIRV) conference entitled “Severe Influenza: Burden, Pathogenesis and Management” wrapped today in Hanoi, Vietnam. The program for the three day conference can be found at this link.

Earlier this week on Monday there was a general press release from the conference regarding the number of human H5N1 cases in Vietnam (FT link).

Originally Posted by Shiloh

Vietnam ranks third in world in human A/H5N1 cases
Tuoitrenews
Updated : Tue, October 30, 2012,1:00 PM (GMT+0700)

With 123 human cases of A/H5N1 avian flu confirmed since 2003, 61 of whom have died, Vietnam now ranks third in the number of flu patients in the world, the Health Ministry reported. . .

Actually, Vietnam dropped to third place in 2011.

Through the end of 2005, Vietnam ranked first with the most confirmed human cases of H5N1 (93). Surprisingly, in the following year, 2006, Vietnam did not record any human cases of H5N1 even though more than 60% of all previous world-wide confirmed cases were reported by Vietnam. It was almost as if Vietnam decided not to have any more human cases of H5N1 in 2006.

In 2006, Vietnam continued to lead the world in number of reported cases with 93, although the count in Indonesia was increasing rapidly. By 2007, Indonesia became the world leader in confirmed H5N1 cases with 117. At that time, Vietnam was second with a total count of 98. Since 2008, Indonesia continues to rank first in the number of WHO-reported H5N1 cases with a total of 191 through October 30, 2012.

Meanwhile, the official case count in Egypt continues to grow since 2006 when the first cases were reported. In 2011, the official cumulative H5N1 count was 158 for Egypt. That number exceeded the cumulative count for Vietnam that year by 39 cases. By the end of 2011, Vietnam had fallen to third among world countries in the cumulative total H5N1 cases reported to WHO.

Is there any significance to ranking countries based on the cumulative number of WHO-reported H5N1 cases?

The WHO data set for H5N1 is small for the 9 year period between 2003 and 2012. But a skeptical interpretation suggests that over the past few years countries with a high incidence of endemic bird flu are becoming more and more reluctant to report or even identify human cases of H5N1. There seems to be tendency among these countries to report fewer and fewer cases with the hope that another county will become the front runner in leading the world in the number of officially reported cases of H5N1.

[Laidback Al]

Egypt - Do Poultry Rearing and Slaughtering Practices Increase Local Human and Poultry Infections?

Egypt has the second highest number of confirmed human cases of H5N1, 168 as of August 10, 2012. Most of these cases were believed to result from non-compliant poultry rearing and slaughtering practices.

An abstract posted by tetano today, entitled Poultry rearing and slaughtering practices in rural Egypt: an exploration of risk factors for H5N1 virus human transmission, suggests that H5N1 transmission between poultry and poultry and humans in Egypt is more complicated.

From the abstract . . .

H5N1 virus prevention in Egypt represents both an epidemiological and socio-cultural challenge. Traditional poultry-rearing practices that likely increase exposures to H5N1-infected poultry are common throughout Egypt. Despite education campaigns following sporadic H5N1 outbreaks, no differences in these practices could be detected between households with previous H5N1 human or poultry cases and those households with any previous experience with H5N1.

The study found that poultry rearing and slaughtering practices did not differ between households experiencing human and poultry H5N1 infections and those households that did not.

It is not clear why H5N1 infections occur in some households and not others, even though H5N1 is endemic in poultry populations in Egypt and the same poultry rearing and slaughtering practices are widespread among the population.

[Gert van der Hoek]

Did not see this Dutch study before, no new conclusion, but IMHO another confirmation from real life, something like a smoking gun:

Conclusion from an analysis of avian influenza virus during a HP H7N7 outbreak:

This implies that HPAI viruses with pandemic potential can emerge directly from poultry.

Comparative analysis of avian influenza virus diversity in poultry and humans during a highly pathogenic avian influenza A (H7N7) virus outbreak.

J Virol. 2011 Oct;85(20):10598-604. Epub 2011 Aug 17.

Abstract

Although increasing data have become available that link human adaptation with specific molecular changes in nonhuman influenza viruses, the molecular changes of these viruses during a large highly pathogenic avian influenza virus (HPAI) outbreak in poultry along with avian-to-human transmission have never been documented.

By comprehensive virologic analysis of combined veterinary and human samples obtained during a large HPAI A (H7N7) outbreak in the Netherlands in 2003, we mapped the acquisition of human adaptation markers to identify the public health risk associated with an HPAI outbreak in poultry.

Full-length hemagglutinin (HA), neuraminidase (NA), and PB2 sequencing of A (H7N7) viruses obtained from 45 human cases showed amino acid variations at different codons in HA (n=20), NA (n=23), and PB2 (n=23).

Identification of the avian sources of human virus infections based on 232 farm sequences demonstrated that for each gene about 50% of the variation was already present in poultry.

Polygenic accumulation and farm-to-farm spread of known virulence and human adaptation markers in A (H7N7) virus-infected poultry occurred prior to farm-to-human transmission. These include the independent emergence of HA A143T mutants, accumulation of four NA mutations, and farm-to-farm spread of virus variants harboring mammalian host determinants D701N and S714I in PB2.

This implies that HPAI viruses with pandemic potential can emerge directly from poultry. Since the public health risk of an avian influenza virus outbreak in poultry can rapidly change, we recommend virologic monitoring for human adaptation markers among poultry as well as among humans during the course of an outbreak in poultry.

Pubmed

[Laidback Al]

This thread is now closed.

Please make additional posts in the thread entitled -

Discussion - Is Bird Flu (H5N1) Still a Global Public Health Threat? (Nov 25, 2012+)